MANUFACTURE OF PREPARATORILY FOAMED GRAIN OF POLYSTYRENE RESIN

摘要

PURPOSE:To prevent preparatorily foamed polystyrene resin grains from being wetted at the time preparatory foaming and to reduce bridging, by atomizing and supplying a treating agent to the resin grains to coat them with the agent when preparatorily foaming the grains. CONSTITUTION:Polystyrene resin grains are supplied to the lower part of a preparatory foaming vessel 4 by a screw feeder 2 and preparatorily foamed to make preparatorily foamed grains. A unit A1 for coating a treating agent such as an alcoholic solution of sorbitan monopalmitate or the like is equipped in a steam duct 11 for supplying steam S to the preparatorily foamed grains. The treating agent is atomized into the preparatory foaming vessel 4 by the flow of the steam so that the atomized agent is dispersed into the flow R of the resin grains. According to this method, a very small quantity of the treating agent can be uniformly coated on the resin grains and the desired preparatorily foamed grains can be continuously and efficiently manufactured.